This error is happening intermittently on different tables. Sometimes it runs the whole project without any of these errors. The columns are Foreign Key Generators on tinyint columns.
RedGate.SQLDataGenerator.Engine.DataGeneration.InvalidColumnDataException: The value '' cannot be inserted
into column Col1 at t.c() at t.Read() at System.Data.SqlClient.SqlBulkCopy.ReadFromRowSource()
at System.Data.SqlClient.SqlBulkCopy.WriteToServerInternal() at
System.Data.SqlClient.SqlBulkCopy.WriteRowSourceToServer(Int32 columnCount) at
System.Data.SqlClient.SqlBulkCopy.WriteToServer(IDataReader reader) at aw.a(CancellableController , Int32 ,
Int32 , ConnectionProperties , GenerateAction , SqlConnection , SDGProject , GenerationReport )